Measurement of the quantum states of squeezed light

Quantum tomography as a tool for the characterization of optical devices

“…The sum sideband modes is then detected as a controlled perturbation attached to the signal beam [3]. The demodulated current is acquired by a digital oscilloscope (Tektronix TDS 520D) with 8 bit resolution and record length of 250000 points per run.…”

“…Possible applications of QHT range from the measurement of photon correlations on a sub-picosecond time-scale [2] to the characterization of squeezing properties [3,4], photon statistics in parametric fluorescence [5], quantum correlations in downconversion [1] and nonclassicality of states [6]. In general, the key point is that QHT provides information about the quantum state within a chosen sideband, thus allowing for a precise spectral characterization of the light beam under investigation.…”

Quantum tomography via equidistant states

“…The determination of quantum states and processes [1] plays an important role in the foundation of quantum theory [4,5] and quantum information theory [6,7,8,9]. Quantum states are mathematical descriptions of physical systems, which provide all the information necessary for characterizing the result of any possible experiment.…”

Adaptive quantum homodyne tomography

“…Among the many state reconstruction techniques suggested in the literature [10][11][12][13][14][15][16][17][18][19], quantum homodyne tomography (QHT) [11][12][13]18] of radiation field have been received much attention [1], being the only method which has been implemented in quantum optical experiments [4,5,11], and recently being extended to estimation of the expectation value of any operator of the field [18], which makes the method the first universal detectors for radiation.…”

“…The possibility of measuring the quantum state of radiation has been received an increasing interest in the last years [1][2][3], as it opens perspectives for a new kind of experiments in quantum optics, with the possibility of measuring photon correlations on a sub-picosecond time-scale [4], characterizing squeezing properties [5], photon statistics in parametric fluorescence [6], quantum correlations in down-conversion [7], nonclassicality of states [8], and measuring Hamiltonians of nonlinear optical devices [9]. Among the many state reconstruction techniques suggested in the literature [10][11][12][13][14][15][16][17][18][19], quantum homodyne tomography (QHT) [11][12][13]18] of radiation field have been received much attention [1], being the only method which has been implemented in quantum optical experiments [4,5,11], and recently being extended to estimation of the expectation value of any operator of the field [18], which makes the method the first universal detectors for radiation.…”